RX 7900 XTX vs RTX 4090 for local AI (2026)
VRAM, memory bandwidth, today's prices (new, used and rental) and which local AI models each card can run.
Prices updated Nov 12, 2026The short version
- VRAM: both have 24 GB, so they fit exactly the same models.
- Speed: the RTX 4090 has about 5% more memory bandwidth, so expect roughly 5% faster token generation on models that fit both (estimate; prompt processing and image generation depend on compute, not shown).
- Price: the RX 7900 XTX is $1,866 cheaper today ($1,200 used vs $3,066 used); per GB of VRAM that's $50 vs $128.
- Software: RX 7900 XTX: ROCm/Vulkan - works in llama.cpp & Ollama; image/video tooling less mature. RTX 4090: CUDA - best support in llama.cpp, vLLM, ComfyUI.
Specs and prices
| RX 7900 XTX | RTX 4090 | |
|---|---|---|
| VRAM | 24 GB GDDR6 | 24 GB GDDR6X |
| Memory bandwidth | 960 GB/s | 1,008 GB/s |
| Memory bus | 384-bit | 384-bit |
| Cheapest today | $1,200 usedGPU Sold · 2026-11-10 | $3,066 usedGPU Sold · 2026-11-10 |
| Lowest new | — | — |
| Used (median eBay ask) | $1,200GPU Sold | $3,066GPU Sold |
| $ per GB VRAM | $50 | $128 |
| Rent from | — | $0.34/hrRunpod |
| Launch MSRP | $999 | $1,599 |
| Launched | 2022-12 | 2022-10 |
| Software | ROCm/Vulkan - works in llama.cpp & Ollama; image/video tooling less mature | CUDA - best support in llama.cpp, vLLM, ComfyUI |
| Check priceused · eBayor new on Amazon | Check priceused · eBayor new on Amazon |
Which models fit
| Model | RX 7900 XTX Q4 | RTX 4090 Q4 | RX 7900 XTX Q8 | RTX 4090 Q8 |
|---|---|---|---|---|
| Llama 3.1 8B Instruct | ✓ ~96 tok/s6.5 GB | ✓ ~101 tok/s6.5 GB | ✓ ~59 tok/s9.9 GB | ✓ ~62 tok/s9.9 GB |
| Llama 3.3 70B Instruct | ✗needs 43 GB | ✗needs 43 GB | ✗needs 73 GB | ✗needs 73 GB |
| Qwen3 8B | ✓ ~93 tok/s6.7 GB | ✓ ~97 tok/s6.7 GB | ✓ ~58 tok/s10.2 GB | ✓ ~61 tok/s10.2 GB |
| Qwen3 14B | ✓ ~55 tok/s10.6 GB | ✓ ~58 tok/s10.6 GB | ✓ ~33 tok/s16.9 GB | ✓ ~35 tok/s16.9 GB |
| Qwen3 32B | ✓ ~26 tok/s21.5 GB | ✓ ~27 tok/s21.5 GB | ✗needs 35 GB | ✗needs 35 GB |
| Qwen3 30B-A3B (MoE) | ✓ ~202 tok/s19.0 GB | ✓ ~213 tok/s19.0 GB | ✗needs 32 GB | ✗needs 32 GB |
| Qwen2.5 Coder 32B Instruct | ✓ ~26 tok/s21.5 GB | ✓ ~27 tok/s21.5 GB | ✗needs 35 GB | ✗needs 35 GB |
| Qwen3 235B-A22B (MoE) | ✗needs 135 GB | ✗needs 135 GB | ✗needs 235 GB | ✗needs 235 GB |
| Gemma 3 12B IT | ✓ ~69 tok/s8.7 GB | ✓ ~73 tok/s8.7 GB | ✓ ~41 tok/s13.9 GB | ✓ ~43 tok/s13.9 GB |
| Gemma 3 27B IT | ✓ ~32 tok/s17.5 GB | ✓ ~34 tok/s17.5 GB | ✗needs 29 GB | ✗needs 29 GB |
| Mistral 7B Instruct v0.3 | ✓ ~105 tok/s6.1 GB | ✓ ~110 tok/s6.1 GB | ✓ ~65 tok/s9.2 GB | ✓ ~68 tok/s9.2 GB |
| Mistral Small 24B Instruct (2501) | ✓ ~36 tok/s15.6 GB | ✓ ~38 tok/s15.6 GB | ✗needs 26 GB | ✗needs 26 GB |
| Mixtral 8x7B Instruct (MoE) | ✗needs 28 GB | ✗needs 28 GB | ✗needs 48 GB | ✗needs 48 GB |
| DeepSeek R1 Distill Llama 8B | ✓ ~96 tok/s6.5 GB | ✓ ~101 tok/s6.5 GB | ✓ ~59 tok/s9.9 GB | ✓ ~62 tok/s9.9 GB |
| DeepSeek R1 Distill Qwen 14B | ✓ ~54 tok/s10.8 GB | ✓ ~57 tok/s10.8 GB | ✓ ~33 tok/s17.1 GB | ✓ ~34 tok/s17.1 GB |
| DeepSeek R1 Distill Qwen 32B | ✓ ~26 tok/s21.5 GB | ✓ ~27 tok/s21.5 GB | ✗needs 35 GB | ✗needs 35 GB |
| FLUX.1 [dev] | ✓ fits9.9 GB | ✓ fits9.9 GB | ✓ fits15.0 GB | ✓ fits15.0 GB |
| FLUX.1 [schnell] | ✓ fits9.9 GB | ✓ fits9.9 GB | ✓ fits15.0 GB | ✓ fits15.0 GB |
| Stable Diffusion XL 1.0 | ✓ fits5.2 GB | ✓ fits5.2 GB | ✓ fits6.3 GB | ✓ fits6.3 GB |
| Wan 2.1 T2V 14B (video) | ✓ fits14.9 GB | ✓ fits14.9 GB | ✓ fits20.9 GB | ✓ fits20.9 GB |
| Wan 2.1 T2V 1.3B (video) | ✓ fits4.6 GB | ✓ fits4.6 GB | ✓ fits5.2 GB | ✓ fits5.2 GB |
8K-token context. tok/s = rough bandwidth-based estimate. Method.
FAQ
Is the RX 7900 XTX or RTX 4090 better for local AI?
VRAM: both have 24 GB, so they fit exactly the same models. Speed: the RTX 4090 has about 5% more memory bandwidth, so expect roughly 5% faster token generation on models that fit both (estimate; prompt processing and image generation depend on compute, not shown). Price: the RX 7900 XTX is $1,866 cheaper today ($1,200 used vs $3,066 used); per GB of VRAM that's $50 vs $128. Software: RX 7900 XTX: ROCm/Vulkan - works in llama.cpp & Ollama; image/video tooling less mature. RTX 4090: CUDA - best support in llama.cpp, vLLM, ComfyUI.
Which has more VRAM, RX 7900 XTX or RTX 4090?
RX 7900 XTX: 24 GB; RTX 4090: 24 GB.
Is the RTX 4090 faster than the RX 7900 XTX for LLMs?
For token generation, likely yes by roughly 5% (memory bandwidth 1,008 vs 960 GB/s). This is an estimate, not a benchmark.
How much do the RX 7900 XTX and RTX 4090 cost today?
RX 7900 XTX: about $1,200 (used, GPU Sold). RTX 4090: about $3,066 (used, GPU Sold). Observed Nov 12, 2026.
More comparisons
Get the weekly GPU price drops
Cheapest card per model, new and used. Free, 1 email a week.
Subscribe on beehiiv →